body {
    width: 100%;
    min-width: 320px;
    max-width: 640px;
    margin: 0 auto;
    font-size: 14px;
    font-family: -apple-system, Helvetica, sans-serif;
    color: #666;
    line-height: 1.5;
    /*行高=子元素字体大小 × 数字（1.5）*/
}

a {
    color: #666;
    text-decoration: none;
}

ul {
    margin: 0;
    padding: 0;
    list-style: none;
}

img {
    vertical-align: middle;
    /*去除图片之间的空白间隙*/
}

div {
    /* css3 盒子模型 */
    box-sizing: border-box;
}

.app {
    height: 45px;
}

.app ul li {
    float: left;
    height: 45px;
    line-height: 45px;
    background-color: #333333;
    text-align: center;
    color: #fff;
}

.app ul li:nth-child(1) {
    width: 8%;
}

.app ul li:nth-child(1) img {
    width: 10px;
}

.app ul li:nth-child(2) {
    width: 10%;
}

.app ul li:nth-child(2) img {
    width: 30px;
    vertical-align: middle;
    /*注意这个属性    行内块 默认与文字底边对其   该属性设置对齐方式*/
}

.app ul li:nth-child(3) {
    width: 57%;
}

.app ul li:nth-child(4) {
    width: 25%;
    background-color: #F63515;
}


/*搜索*/

.search-wrap {
    position: fixed;
    /*改成固定定位 可以让下面盒子的图片 上移    固定定位一定要有宽度*/
    overflow: hidden;
    /*解决子集盒子外边距合并问题*/
    height: 44px;
    width: 100%;
    min-width: 320px;
    max-width: 640px;
}

.search-btn {
    position: absolute;
    top: 0;
    left: 0;
    width: 40px;
    height: 44px;
}

.search-btn::before {
    content: '';
    display: block;
    width: 20px;
    height: 18px;
    background: url(../images/s-btn.png) no-repeat;
    background-size: 20px 18px;
    margin: 14px 0 0 15px;
}

.search-login {
    position: absolute;
    top: 1px;
    right: 5px;
    width: 40px;
    height: 44px;
    color: #fff;
    text-align: center;
    line-height: 44px;
}

.search {
    position: relative;
    margin: 5px 50px 0;
    height: 34px;
    border-radius: 20px;
    background-color: #fff;
}

.jd-icon {
    position: absolute;
    top: 10px;
    left: 15px;
    width: 20px;
    height: 15px;
    background: url(../images/jd.png) no-repeat;
    background-size: 20px 15px;
}

.jd-icon::after {
    content: "";
    display: block;
    position: absolute;
    top: 0px;
    right: -8px;
    width: 1px;
    height: 15px;
    background-color: #ccc;
}

.sou {
    position: absolute;
    top: 10px;
    left: 50px;
    width: 20px;
    height: 15px;
    /*二倍精灵图的用法： 先在测量工具FW等比例缩小二倍，
	 * 然后再测量坐标，最后在background-size中写下缩小二倍后的精灵图的宽度*/
    background: url(../images/jd-sprites.png) no-repeat -81px 0;
    background-size: 200px auto;
}

.slider img {
    width: 100%;
}


/*小家电*/

.brand {
    overflow: hidden;
    /*因为边框圆角给的是盒子  要想图片有圆角  把多余部分隐藏*/
    border-radius: 10px 10px 0 0;
}

.brand div {
    float: left;
    width: 33.33%;
}

.brand div img {
    width: 100%;
}


/*nav*/

nav {
    overflow: hidden;
    padding-top: 5px;
}

nav a {
    float: left;
    width: 20%;
    text-align: center;
}

nav a img {
    margin: 10px 0;
    width: 40px;
}

nav a span {
    display: block;
}


/*news*/

.news {
    margin-top: 20px;
}

.news a {
    float: left;
    box-sizing: border-box;
}

.news img {
    width: 100%;
}

.news a:nth-child(1) {
    width: 50%;
}

.news a:nth-child(2),
.news a:nth-child(3) {
    width: 25%;
    border-left: 1px solid #ccc;
}